Answer:
Correct choice is B
Step-by-step explanation:
All given options represent quadratic function. Let the equation of this quadratic function be
Then
1.
2.
3.
Solve the system of two equations:
Then
Thus, the equation of the function is
Note that
Answer:
x=-2 (the actual solution)
x=-5 (the extraneous solution)
Step-by-step explanation:
First step is to isolate the radical part (the part with the square root).
So we will add 4 on both sides first:
To get rid of square we are going to square both sides:
We are going to expand right hand side (you can use "F.O.I.L":
Subtract x on both sides and subtract 6 on both sides:
Combine like terms:
We will now factor:
(Since 2(5)=10 and 2+5=7)
Set both factors equal to 0:
x+2=0 or x+5=0
Solve first equation by subtracting 2 on both sides to obtain x=-2.
Solve second equation by subtracting 5 on both sides to obtain x=-5.
Now let's check to see if these are both actually indeed solutions to the equation we began with:
for
:
is a true equation so
is indeed a solution.
for
:
is false so
is what we call the extraneous solution.